Guide

Topsoil vs Fill Dirt vs Compost

The difference between topsoil, fill dirt and compost, and when to use each.

These three look similar in a pile but do very different jobs.

Topsoil

The upper layer of soil, screened for use, with some organic content. Use it to build beds, level a lawn, or top up planting areas. It runs roughly 1.1 tons per cubic yard when fairly dry.

Fill dirt

Subsoil with little organic matter, used to fill holes, raise grades and build up low spots. It is cheaper than topsoil and compacts well, but plants will not thrive in it.

Compost

Decomposed organic matter, rich in nutrients. Mix it into topsoil to improve beds rather than using it alone, since pure compost is too rich and drains too fast for most plantings.

Estimate your soil. Topsoil Calculator →

Common questions

Can I grow plants in fill dirt?

Not well. Fill dirt is for raising grades and filling holes. Use topsoil, ideally amended with compost, for planting.

How much does topsoil weigh?

Roughly 1.1 tons per cubic yard when fairly dry, more when wet.
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